English
Note the following information:
• When using float switches, ensure that they can move
freely in the operating area.
• The water level must not fall below the minimum.
• The maximum starts per hour may not be exceeded.
• If the fill levels fluctuate strongly, then a level control
should be made on two test points as standard. This
means larger differential gaps are reached.
Installation
For correct installation, please see the installation and operation
manual for the level control device.
observe the information on the maximum starts per
hour and the minimum water level.
5.5.
Dry-running protection
To guarantee the necessary cooling, the unit must be submerged
in the pumped fluid, depending on the operating mode. Also make
sure that no air enters the hydraulic housing.
The product must therefore always be submerged in the pumped
liquid up to the top edge of the hydraulic housing or the motor
housing. For optimum reliability, we recommend installing a
dry-run protection system.
Correct running is ensured by float switches or electrodes. The
float switch or electrode is fixed in the shaft and switches off the
machine when the water level falls below the minimum cover-
age level. If the dry-run protection only consists of one float or
electrode, the unit may turn on and off constantly if filling levels
fluctuate strongly. This can result in the maximum number of
motor start-ups (switching cycles) being exceeded.
5.5.1. Corrective measures for avoiding excessive
switching cycles
• Manual reset
The motor is switched off when the water level falls below
the minimum coverage level and switched back on when a
sufficient water level is reached.
• Separate reactivation point
A second switching point (additional float or electrode)
is used to obtain a sufficient difference between the
activation and deactivation points. This prevents constant
switching. This function can be put into effect with a level
control relay.
5.6.
Electrical connection
ELECTRoCUTIon hazard!
Incorrect electrical connections can cause fatal
electric shocks. Electrical connections may only
be carried out by a qualified electrician who is ap-
proved by the local power supplier, in accordance
with locally applicable regulations.
• The mains current and voltage must be as stated on the
name plate.
• Connect the power supply cable in accordance with the
applicable standards and regulations and according to the
wire assignment.
• Any available monitoring equipment, e.g. for the motor
temperature, must be connected and tested to ensure that
it is working properly.
• For three-phase current motors, a clockwise rotating field
must be available.
• Ground the product properly.
Products that are permanently installed must be grounded
in compliance with nationally applicable standards. If a
separate grounding conductor is available, it must be con-
nected to the marked hole or grounding terminal (;) using
a suitable screw, nut, toothed washer and flat washer. The
cross section of the cable for the grounding conductor
connection must correspond to the local regulations.
• A motor protection switch must be used for motors with
a free cable end. We recommend using a residual current
device (RCD).
• Switching devices must be purchased as accessories.
5.6.1. Mains fuses
The pre-fusing must be rated according to the starting currents.
You will find the starting currents on the name plate.
Only slow-blow fuses or K characteristic automatic cut-outs may
be used for pre-fusing.
5.6.2. AC motor
Fig. 4.: Connection plan
L
Mains supply
N
20
Bimetal sensor
21
The AC version has a capacitor switching device (operating capac-
itor) and free cable ends.
The connection to the mains is made at the switch box terminals.
Electrical connections may only be made by a quali-
fied electrician!
The wires of the connection cable are assigned as follows:
7-wire connection cable
Wire number
Terminal
1
Temperature monitor for winding
2
3
L (U1/Z1)
4
N (U2)
Z2 - connection for the operating ca-
5
pacitor
6
Seal integrity monitor for motor chamber
Green/yellow
Ground (PE)
If the unit has a plug, it is connected to the electricity supply by
plugging it into the electricity socket.
46
Seal integrity monitor for
DK
motor chamber
Cr Operating capacitor
PE Ground